Liquid switch



Oct. 30, 1928.

J. R. JACKSON, JR

LIQUID SWITCH Original Filed April 25-, 1924 2 Sheets-Sheet 1 Jose@R.Jac?c@on,J?a

Invenior Patented Oct. 30, 1928.

UNITED STATES PATENT OFFICE.

JOSEPH B. JACKSON, .13., OF BROOKLINE, MASSACHUSETTS, ASSIGNOR TOMARGUERITE E. JACKSON, OF BOSTON, MASSACHUSETTS.

LIQUID SWITCH.

Application filed April 25, 1924, Serial No. 708,902. Renewed August 24,1928.

This invention aims to improve circuit breakers and its object is toprovide a simple device adapted to make and break high and low tensioncircuits without arcmg.

In the drawings which show certain lllustrative embodiments of myinvent1on:

Fig. 1 is an elevation of the preferred form of switch;

Fig. 2 is a vertical and substantially central section of the device andlooking 1n the same direction as in Fig. 1;

Fig. 3 is a transverse section taken on the line 33 of Fig. 2;

Fig. 4 is a vertical transverse section of a modified form of switch;

Fig. 5 is a vertical section of the form shown in Fig. 4 takensubstantially at right angles to the section of Fig. 4; and

' Fig. 6 is a vertical transverse section of still another form of theinvention,

In the drawings, referring part1cularly to Figs. 1 to 3 inclusiie 1 is ahollow rotatable body or casing preferably formed 1n two parts 2 and 3secured together along a central seam 4 herein by bolts 5. The sections1 and 2 are shown as having trunnions 6 ournalled to rock in bearings 7supported on a suitable base 8. The casing 1 may be formed of anyappropriate material preferably metal for strength and is provided withan operatin member such for example as a handle ilounted within thecasing 1 is a 11I11I1g 10 of appropriate insulating material which issupported and protected by the two part casing 1, thus preventingbreaklng of said msulating lining.

The lining 10 contains a mass of conduct ng liquid such, for example, asmercury which is preferabl separated into a predetermined number ofodies, herein two, 11 and 12 by a non-conducting partition 13preferably, though not essentially, a part of the lining 10 and arrangedto separate the interior of said casing into substantially two equallyproportioned compartments. The bodies of mercury 11 and 12 onlypartially fill the said compartments and preferably occupy less thanhalf the space thereof. Moreover the two bodies of mercury 11 and 12preferably constitute terminals for an electric circuit to completewhich it is desirable to make connection between said bodies, they beingnormally separated by the insulating partition 13.

This connection may be made in many ways but, for convenience, I haveshown within the partition 13, an opening 14 of any appropriate sha eand located so as normally to be removed cm the mercury but when it isdesired to close the circuit includin said mercury, said casing 1 may berocked so as to submerge said opening in the mercury and allow the twoparts thereof to be united.

In most liquid switches of the character herein shown difliculty hasbeen experienced, due to the arcing of the current from one body ofmercury to the other during the making and breaking of the connectionbetween said bodies, but to remove this objection in the presentinventiomthe remaining spaces in the compartments containing the bodiesof mercury 11 and 12 are preferably filled with .a suitable currentresisting fluid 15 such, for

example, as silica jell which renders it difficult and substantia lyimpossible for the current to are through the opening 1 1 when thelatter is surrounded by the non-conducting liquid.

To facilitate the union of the bodies of mercury through the opening 14and to eliminate possible gaps or pockets being formed within the liquidwhen the casing is rocked, the edges around said opening are preferablybeveled as indicated at 16 and-it is to be understood that although thesaid opening is shown as of rectangular form, this opening is notlimited to the exact contour shown.

The passing of a current of electricity through liquids, particularly inswitches of the type disclosed, often generates considerable heat withthe consequent expansion of said liquids and to allow for such expansionmeans are provided preferably consistin of corrugated metal plates 17having t eir marginal portions suitably supported so as to preventleakage of the liquid contents of the lining 10. These plates arepreferably disposed at sufficient distance from the sides of the housingsections 2 and 3 to allow said plates to bulge laterally to compensatefor the maximum expansion of the liquids contained within said casing,thus acting as diaphragms which possess suflicient elasticity to restorethe liqulds to their proper positionsupon contraction thereof.

Any appropriate connection may be made between the masses 11 and 12 ofmercury and the electrical conductors but preferably I have providedbinding osts 18 in the diaphragms 17 to which inding posts the ends 19of said conductors may be led, herein through openings 20 in thetrunnions 6 of said housing.

In the embddiment of the invention just described the mercury or otherconducting liquid is shown in two se arated insulating bodies. It is,however, to e understood that the invention is not limited to thisarrangement and in Figs. 4 and 5 a modified form of the invention isshown wherein the mercury or other conducting liqpid 21 is retained in asingle mass within a ollow rotatable body 22 preferably made intwo parts23 and 24 similar, if desired, to the form shown in Figs. 1 to 3inclusive, said hollow body havin trunnions 25 journalled to rock insuitable bearings such, for example, as in the case hereinbeforedescribed. The hollow body 22 may and preferably does contain an innercasing 26 composed of appropriate nonconducting material and hereincomprises a cylindrical part 27 and a closing end wall 28 formedintegral with said cylindrical part.

The cylindrical part 27 also includes an annular flange 29 which is, inthe present example, adapted to be clamped between the two sections 23and 24 of the rotatable body 22, thus centrally and securely positioningsaid inner housing so as to insure its movement with the said outer bodywhen the latter is rocked by means of the handle 30 or otherwise.Substantially as in the previous case the mercury 21 only partiallyfills the interior of the casing 26, the remaining portion of saidcasing being preferably occupied by any appropriate non-conductingliquid, said mercury and said non-conducting liquid being retained inthe inner housing 26 herein b a metallic corrugated end plate 32 secureto the rim of the cylindrical part 27 in any appropriate manner toprevent escape of the liquid from said inner casing.

Secured to the corru ated end 32 of said inner housing is a binding post33 to which one terminal 34 of the electric circuit is attached. Themetal partition or plate 32 is preferably also in electrical contactwith the mercury 21 and to provide for an interrupted connection betweenthe terminal 34 of the electric circuit and the other terminal, hereinshown at 35, a switch blade 36 is suitably supported herein in theinsulating wall 28 of said inner housing by a screw 37 extending throughsaid end wall 28 and through an insulating core 38 into engagement withthe blade 36, the end of which is preferably embedded in said insulatingcore 38, said screw 37 constituting a binding post for the terminal wire35.

The blade 36 may be of any appropriate shape but herein its edges arebevelled so as to cut the liquid through which it is moved withoutcauslng undue disturbance thereof. This blade is secured to therotatable hollow body hereinbefore described in such a manner and insuch a position that it will normally lie outside of the mercury 21 andfar enough therefrom to prevent any arcingof the current from said bladeto said mercury but upon relative movement of said casing and saidmercury, said blade will be moved into submerged relation to saidmercury and thus effect the closing of the electric circuit and withoutthe arcing of the current as in most cases of liquid circuit breakers.

It is to be understood that the invention is not limited to expansiblecontainers for the mercury and non-conducting liquids and in Fig. 6 Ihave illustrated a modified construction wherein the outer casing 39which may be substantially similar to those hereinbefore described, isprovided with an insulating interior or inner portion 40 preferably madein two parts 41 and 42 united centrally of the casing and adapted to beheld in proper relation by the bolts 43 uniting the two parts of saidcasing 39.

The casing 40 contains the usual supply of mercury 44 and a supply ofnon-conducting fluid 45 which does not quite fill the container 40allowing a space 46 at the top for expansion of the liquid due to heatcreated by the passing of said electric current through said liquid.

Switches, preferably knife blades 47 and 48, are secured respectively tothe side walls 49. 50 of said inner housing herein by terminal studs 51,51 similar to the studs 37 in the form shown in Fig. 4, said studs 51constituting binding posts for the terminal wires 52 of the electriccircuit. As the casing 39 is rocked about its axis the blades 47 and 48are immersed at the proper times in the mercury 44, thus effecting theclosing of the electric circuits, said blades being separated from eachother a sufiicient distance to prevent any arcing therebetween andalthough said blades are shown as being substantially in alignment so asto enter the liquid at approximately the same time it is distinctl to beunderstood that the invention is not limited to this arrangement.

While I have herein shown and described merely for illustrativepurposes, certain specific embodiments of my invention and havedisclosed and discussed in detail the construction and arrangementincidental to such disclosure, it is to be distinctly understood thatthe invention is limited neither to the mere details or relativearrangement of the parts nor to the specific application herein shown,but that extensive variations from the illustrations may be made withoutdepa ting from the principles thereof.

Claims:

1. A switch comprising a hollow body, normally disconnected currentconducting elements arranged within said hollow body, means forelectrically connecting and disconnecting said elements includingconducting lllU liquid, a non-conducting fluid substantially filling theremaining portions'of said hollow body to prevent arcing duringthejconnecting and'jdisconnecting operations of said switch andmeans toallow for expansion and contraction of the contents of "said hollowbody.

2, A switch comprising a hollow body, a

current conducting liquid partially filling' said hollow body, means insaid casing to cooperate with said liquid in making andinterrupting anelectric circuit through said liquid, means for effecting relativemovement between said cooperating means and said liq-J uid, a fluidsubstantially filling the remain-- ing spaces in said hollow bodyadapted to prevent arcing during said circuit making and breakingoperations and means to allow for expansion and contraction of the con-"tents of said hollow body.

3; A switch comprising a hollow body, a current conducting liquidpartially filling saidhollo'w body, means in said casing to 00- operatewith said liquid in making and interrupting an electric circuit throughsaid liqu1d, means for effecting relative movement between saidcooperating meansa-nd; said liq uid, a fluid substantially filling theremain ing space in said hollow body adapted to prevent arcing duringsaid circuit-making and breakingiop'erations and anlexpansible portionfor said hollow body adapted to allow 'for'expansion and contraction ,ofsaid contents of said casing.

4. A. switch comprising'a hollow rotatable body, two normally Insulatedbodies of current conducting liquid partially filling said body, meansfor uniting said conductin liq- 111d at selected points in the-rotationofsaid' 40.

hollow body and a nonconducting liquid'substantially filling theremaining portions'of said hollow body for preventing the arcing of anelectric current during theuniting and separating of said bodies ofconducting liqsubstantially filling the; remaining portion of saidhollow body for preventing the arcing of w an electric-current duringthe uniting andsep arating-of said bodies of conductingliquid',

said rotatable body having at least one cor rugated metallic walladapted to yield during the expansion of the liquid contained in saidbody.

a '6'. A'switch-comprising a hollow rotatable body composedlargelyof'ins'ulating material, a partition of insulatingmaterial dividing saidbody into two. compartments, said partition having atleast one orificefor providing communication between said com-'- partments, a body ofmercury partially fillmg each of said-compartments and adapted to beunited when said orifice is in submerged relation with said mercury,said hollow body having at least one expansible wall to'allow dyia .7

- A switch-comprising a hollow rotatable body composedlargely ofinsulating mate rial, at least one partit on of insulating material fordividing' said' body into compartmerits, said partition having atleastone or p fice for providing communication" between said compartments, abody of. mercury par-i for expansion of the contents of said hollow;

tially fill'ing said compartments and adapted to be united when anorifice is submerged in said mercury by rotation of said'hollow bod theside walls of said rotatable hollow bo y being composed of flexiblemetal adaptedto yield upon expansion by heat of the contents of saidcompartments, said-side walls alsoconstituting the terminals of anelectric circuit and in constant electrical communication with saidmercury. 5

8; A switch comprising a .hollow 'body composed largely of insulatingmaterial, at 1 least one partition of insulatingmaterial separating saidinsulatin' material into parts normally electrically disconnected witheach other, means in said hollow body adapted to electrically connectand disconnect said parts J ofinsulating material and at least oneresilient wall to said hollow body adapted to expand and contract toallow for the expansion ;and contraction of the contents of said" 1101-low' body. v In-testimony whereof, I have signed my name to thisspecification. I 1 JOSEPH R. JACKSON, JR.

